Carbureter.



O. C. FUNDERBURK.

CARBURETER.

APPLICATION FILED OCT. 8. 1914.

11. a 15 1 7780 1 Patented Aug. 31, 1915.

2 SHEETS-SHEET I.

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0. C. FUNDERBURK.

CAHBURETER.

APPLICATION FILED acne. $914.

1 1 5 1 7780 Patented Aug. 31, 1915.

2 SHEETSSHEET 2.

WITNESSES: INVENTOR %mw By WM 1 JV A TTORNEYS UNITED STATES PATENT OFFICE.

OTIS C. FUNDERBURK, OF DETROIT, MICHIGAN, ASSIGNOR T0 DETROIT LUBRICATOB COMPANY, OF DETROIT, MICHIGAN, A CORPORATION OF MICHIGAN.

CARBUIRETEB.

Application filed October 8, 1914.

To all whom it may concern Be it known that I, OTIS C. FUNDERBURK, a citizen of the United States of America, residing at Detroit, in the county of Wayne and State of Michigan, have invented certain new and useful Improvements in Carbureters, of which the following is a specification, reference being had therein to the accompanying drawings.

It is the object of the invention to obtain a greater flexibility in operation, or, in other words, to obtain a construction which will quickly respond as to any adjustment of the throttle by a corresponding change in the flow of liquid fuel. Heretofore great difficulty has been experienced in increasing the flow of oil when the throttle was suddenly opened, due to the greater inertia of the liquid than that of the air. Thus the unavoidable lack in the discharge of oil will result in the formation of an impoverished explosive mixture. With the presentinvention ll have overcome this d-ifliculty by providing a conduit connecting with the mixing chamber which normally is in communication with the external atmosphere and discharges air only, together with means operating upon a sudden opening of the throttle for discharging oil to said conduit and maintaining the discharge for a limited time.

In the drawings, Figure l is a sectional side elevation of the carbureter to which my improvements are applied; Fig. 2 is a plan view thereof; Fig. 3 is a central lon-, gitudinal section; and Fig. 4: is a section on line mw Fig. 2.

A is the body of the carbureter contain ing the air and oil mixing meansemployed during the normal operation and which forms no part of the present invention.

B is a chamber above the, body A, in which the commingling is completed, and C is the throttle valve above the chamber B.

D is the chamber for the float valve provided with suitable connections, not shown, to the carbureter body.

E is a conduit. the upper end of which extends into the chamber B, while the lower end communicates with a tubular casing F. This casing F, as shown, is arranged in the space between the body of the carbureter and the float chamber, and its upper end communicates with the external atmosphere through a port Gr.

Specification of Letters Patent.

Patented Aug. 31L, 1915..

Serial No. 865,623.

H is a second tubular casing, which, as shown, is arranged parallel to the casing F on the opposite side of the central plane of the carbureter body. This casing H is connected at its lower end by a port I with the Oll space in the float chamber, while its upper end is connected with the air space in said float chamber as indicated at H, so that normally the level of oil in the float chamber will be maintained also in the easing H.

J is a siphon, one leg J of which extends downward in the casing H to near the lower end thereof, while the other leg J extends in the casing F to a slightly greater depth. The bend in the siphon is normally above the level of oil, and consequently the oil will not flow without some means of start mg. The upper or discharge end of the conduit E is provided with a restricted discharge nozzle K suitably proportioned to the size of air port G in the casing F, and there is also a restricted passage between the chamber H and the port I from the float chamber, which, as shown, is formed by a plug L having a restricted bore L and located in the lower portion of the casing H between the port I and the lower end of the leg J of the siphon. This plug 1L may be inserted through the lower end of the case which is provided with a removable cap M.

In the operation of the carbureter the pressure within the chamber B is only slightly less than that of the external atmosphere which results in the flow of the column of air entering the port G passing downward through the casing F and then upward through the conduit E to the discharge nozzle K thereof, and from the latter discharging into the mixing chamber. This flow of air will continue as long as the carbureter is operating uniformly or where any adjustment of the throttleis gradual. If, however, the throttle is suddenly opened this will lower the pressure in the chamber B by placing the same in communication with the higher vacuum above the valve, which in turn will result in an acceleration in the flow of airthrough the conduit E. As the air is supplied through the atmospheric port G, there will be a lowering in the pressure within the casing 1F, and the ports are so proportioned that this lowering of pressure will raise the level of oil in the tube J above the bend, or, in other words, will start the siphon. When the siphon is once started it will continue to flow, the oil accumulating in the bottom of the chamber F, from which it is drawn out through the conduit E and discharged through the nozzle K into the mixing chamber. The flow of oil will decrease the height in the chamber H, and although this chamber is constantly supplied with oil'through the port I and restricted passage L, the latter restriction is sufficient to restrict the inflow more than the outflow. Consequently the oil level in the casing II will fall below the lower end of the leg J, whereupon the siphon is broken and the oil flow ceases.

It will be readily understood that any desired quantity of oil may be sodischarged by properly proportioning the various ports and passages and furthermore, by providing exchangeable plugs L with the ports L thereof, varied in size, the operation of the carbureter may be modified.

What I claim as my invention is 1. In a carbureter, the combination with a casing containing a mixing chamber, of a conduit discharging into said mixing chamber constantly in communication with the atmosphere and normally discharging ai-r only, and means operating upon a sudden lowering in pressure in said mixing chamber for discharging a limited quantity of oil therethrough.

2. In a carbureter, the combination with the casing containing a mixing chamber, of a conduit communicating with said mixing chamber normally open to the atmosphere and dischargin air only into said chamber, of means operating on a sudden lowering of pressure in said chamber for flooding said conduit with a limited quantity of oil and discharging the same to said chamber.

3. In a carbureter, the combination with a mixing chamber, a suction conduit and a throttle between the same, of a conduit connecting with said mixing chamber below said throttle having external communication with the atmosphere and normally discharging into said chamber air only,'and means operating upon the sudden opening of said throttle for floodin said conduit with a limited quantity of oil and discharging the same into said chamber.

4:. In a carburetor, the combination with a casing containing a mixing chamber, of a conduit connecting with said mixing chamber and open at its opposite end to the atmosphere to normally discharge only air into said chamber, a well forming a portion of said conduit, and a siphon for discharging oil into said well adapted to be started by the lowering of pressure in said mixing chamber.

5. In a carbureter, the combination with a casing containing a mixing chamber, of a conduit connected to said chamber having a restricted discharge thereinto and an atmospheric opening at its opposite end, with a differential restriction, a well forming a portion of said conduit, an oil siphon having its discharge leg depending in said well, the ratio between the restricted inlet and restricted discharge being such as to normally flow air only through said conduit without starting the siphon and to start the siphon upon an abnormal lowering of air pressure in said chamber.

6. In a carbureter, the combination with a casing containing a mixing chamber and a reservoir containing a normal level of oil, of a conduit connecting with said mixing chamber extending downward below the oil level and upward to at atmospheric connection, a siphon. having its inlet leg immersed in oil and its discharge leg in the portion of said conduit intermediate said restricted inlet, and restricted discharge, the ratio of restrictions being such as to normally maintain in said conduit a pressure drop insufficient to start said siphon and to increase said drop to the siphon starting point upon an abnormal lowering of pressure in said mixing chamber.

7. In a carburetor, the combination with a casing containing a mixing chamber and a reservoir containing a normal level of oil, of an auxiliary reservoir for a limited supply of oil having a restricted connection with the main reservoir and also an atmospheric connection, a conduit communicating with said mixing chamber extending downward below the level of oil and upward above the oil level to a restricted atmospheric connection, and a siphon having its inlet leg in said auxiliary oil reservoir and its discharge leg in said conduit intermediate the inlet and discharge, the various restrictions being so proportioned that air only will normally be discharged through said conduit and without the pressure drop .therein will be suflicient to start said siphon, and upon an abnormal lowering of pressure in the mixing chamber the pressure drop in said conduit will be increased to the siphon-starting point.

8. In a carbureter, the combination with a casing containing a mixing chamber, of means for initiating a discharge of oil into the mixing chamber, upon a sudden lowering of pressure in said chamber, and for maintaining said flow for a limited time, despite variations in pressure during such time.

9. In a carbureter, the combination with a casing containing a mixing chamber, of a conduit discharging into said chamber open to the atmosphere and normally discharging air only into said chamber, and means operating on a sudden lowering in pressure in said chamber for flooding said conduit with a limited quantity of oil between its outlet and air inlet.

10. In a carbureter the combination with a casing containing a mixing chamber, and two adjacent wells, one containing a normill level of oil and the other normally empty and having an air inlet in its upper portion, of a conduit communicating with the lower end of the normally empty well and with the mixing chamber, and means actuated by a sudden falling of pressure in the mixing chamber for discharging the contents f the full Well into the empty well.

In testimony whereof I afiix my signa- 15 ture in presence of two witnesses.

OTIS C. .FUNDERBURK. lVitnesses \VM. J. BELKNAP, JAMES P. BARRY. 

